   * {
            margin: 0;
            padding: 0;
        }

        body {
            width: 100vw;
            height: 100vh;
            overflow: hidden;
        }
        .photo img {
            position: absolute;
            width: 110vw;
            height: 110vh;
            /* 这里的translate属性值必须是-(width-100vw/2) */
            transform: translate(-5vw, -5vh);
            transition: 1.2s linear;
        }


        #login {

            height: 100vh;
            width: 20vw;
            background-color: rgba(22, 22, 22, 0.5);
            position: absolute;
            border-top: #34495e solid 3px;
            border-bottom: #34495e solid 3px;
            display: flex;
            flex-direction: column;
            justify-content: space-between;
        }
        
        #login h1 {
            color: white;
            line-height: 2em;
            font-size: 5rem;
        }

        #login form {
            width: 100%;
        }

        #login form a {
            cursor: pointer;
        }

        #login form input {
            margin: 1vh 0;
            width: 60%;
            font-size: 1rem;
            border: none;
            background-color: rgba(255, 255, 255, 0.8);
        }

        #login form .warp {
            width: 60%;
        }

        #login form .warp a {
            display: block;
            margin: 1vh auto;
            width: 25%;
            background-color: white;
            border-radius: 10px;
            text-align: center;
            color: rgba(0, 0, 0, 0.8);
            font-size: 1rem;
            text-decoration: none;
            background-color: rgba(255, 255, 255, 0.8);
        }

        .piece_2 {
            background-color: rgba(22, 22, 22, 0.5)
        }

        #login .piece_2 {

            color: white;
            line-height: 3rem;
            font-size: 1rem;
            display: flex;
            justify-content: space-around;
        }

        @media (max-width:1000px) {

            #login {
                height: 100vh;
                width: 100vw;
            }
          
            #background {
                position: absolute;
                width:auto;
                height:100vh;
                transform: translate(0, 0);
            }
            .photo{
                position: absolute;
                height:100vh;
                width:100vw;
               overflow: hidden;
            }
            .piece_1{
                margin:0 auto
            }
            #login form .warp a {
                width:20vw;
            }
        }